Exemplo n.º 1
0
MonoMethod*
mono_gc_get_write_barrier (void)
{
  MonoMethod *res;
  MonoMethodBuilder *mb;
  MonoMethodSignature *sig;

  if (write_barrier_method)
    return write_barrier_method;

  /* Create the IL version of mono_gc_barrier_generic_store () */
  sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
  sig->ret = &mono_defaults.void_class->byval_arg;
  sig->params [0] = &mono_defaults.int_class->byval_arg;

  mb = mono_mb_new (mono_defaults.object_class, "wbarrier", MONO_WRAPPER_WRITE_BARRIER);

  mono_mb_emit_ldarg (mb, 0);
  mono_mb_emit_icall (mb, (void*)mono_gc_wbarrier_generic_nostore);
  mono_mb_emit_byte (mb, CEE_RET);

  res = mono_mb_create_method (mb, sig, 16);
  mono_mb_free (mb);

  //FIXME locking
  write_barrier_method = res;

  return write_barrier_method;
}
Exemplo n.º 2
0
/* FIXME: Do this in the JIT, where specialized allocation sequences can be created
 * for each class. This is currently not easy to do, as it is hard to generate basic 
 * blocks + branches, but it is easy with the linear IL codebase.
 *
 * For this to work we'd need to solve the TLAB race, first.  Now we
 * require the allocator to be in a few known methods to make sure
 * that they are executed atomically via the restart mechanism.
 */
static MonoMethod*
create_allocator (int atype)
{
	int p_var, size_var;
	guint32 slowpath_branch, max_size_branch;
	MonoMethodBuilder *mb;
	MonoMethod *res;
	MonoMethodSignature *csig;
	static gboolean registered = FALSE;
	int tlab_next_addr_var, new_next_var;
	int num_params, i;
	const char *name = NULL;
	AllocatorWrapperInfo *info;

#ifdef HAVE_KW_THREAD
	int tlab_next_addr_offset = -1;
	int tlab_temp_end_offset = -1;

	MONO_THREAD_VAR_OFFSET (tlab_next_addr, tlab_next_addr_offset);
	MONO_THREAD_VAR_OFFSET (tlab_temp_end, tlab_temp_end_offset);

	g_assert (tlab_next_addr_offset != -1);
	g_assert (tlab_temp_end_offset != -1);
#endif

	if (!registered) {
		mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
		mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
		registered = TRUE;
	}

	if (atype == ATYPE_SMALL) {
		num_params = 1;
		name = "AllocSmall";
	} else if (atype == ATYPE_NORMAL) {
		num_params = 1;
		name = "Alloc";
	} else if (atype == ATYPE_VECTOR) {
		num_params = 2;
		name = "AllocVector";
	} else {
		g_assert_not_reached ();
	}

	csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
	csig->ret = &mono_defaults.object_class->byval_arg;
	for (i = 0; i < num_params; ++i)
		csig->params [i] = &mono_defaults.int_class->byval_arg;

	mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
	size_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
	if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
		/* size = vtable->klass->instance_size; */
		mono_mb_emit_ldarg (mb, 0);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoVTable, klass));
		mono_mb_emit_byte (mb, CEE_ADD);
		mono_mb_emit_byte (mb, CEE_LDIND_I);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoClass, instance_size));
		mono_mb_emit_byte (mb, CEE_ADD);
		/* FIXME: assert instance_size stays a 4 byte integer */
		mono_mb_emit_byte (mb, CEE_LDIND_U4);
		mono_mb_emit_stloc (mb, size_var);
	} else if (atype == ATYPE_VECTOR) {
		MonoExceptionClause *clause;
		int pos, pos_leave;
		MonoClass *oom_exc_class;
		MonoMethod *ctor;

		/* n > 	MONO_ARRAY_MAX_INDEX -> OverflowException */
		mono_mb_emit_ldarg (mb, 1);
		mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
		pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
		mono_mb_emit_exception (mb, "OverflowException", NULL);
		mono_mb_patch_short_branch (mb, pos);

		clause = mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
		clause->try_offset = mono_mb_get_label (mb);

		/* vtable->klass->sizes.element_size */
		mono_mb_emit_ldarg (mb, 0);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoVTable, klass));
		mono_mb_emit_byte (mb, CEE_ADD);
		mono_mb_emit_byte (mb, CEE_LDIND_I);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoClass, sizes.element_size));
		mono_mb_emit_byte (mb, CEE_ADD);
		mono_mb_emit_byte (mb, CEE_LDIND_U4);

		/* * n */
		mono_mb_emit_ldarg (mb, 1);
		mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
		/* + sizeof (MonoArray) */
		mono_mb_emit_icon (mb, sizeof (MonoArray));
		mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
		mono_mb_emit_stloc (mb, size_var);

		pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);

		/* catch */
		clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
		clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
		clause->data.catch_class = mono_class_from_name (mono_defaults.corlib,
				"System", "OverflowException");
		g_assert (clause->data.catch_class);
		clause->handler_offset = mono_mb_get_label (mb);

		oom_exc_class = mono_class_from_name (mono_defaults.corlib,
				"System", "OutOfMemoryException");
		g_assert (oom_exc_class);
		ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
		g_assert (ctor);

		mono_mb_emit_byte (mb, CEE_POP);
		mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
		mono_mb_emit_byte (mb, CEE_THROW);

		clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
		mono_mb_set_clauses (mb, 1, clause);
		mono_mb_patch_branch (mb, pos_leave);
		/* end catch */
	} else {
		g_assert_not_reached ();
	}

	/* size += ALLOC_ALIGN - 1; */
	mono_mb_emit_ldloc (mb, size_var);
	mono_mb_emit_icon (mb, ALLOC_ALIGN - 1);
	mono_mb_emit_byte (mb, CEE_ADD);
	/* size &= ~(ALLOC_ALIGN - 1); */
	mono_mb_emit_icon (mb, ~(ALLOC_ALIGN - 1));
	mono_mb_emit_byte (mb, CEE_AND);
	mono_mb_emit_stloc (mb, size_var);

	/* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
	if (atype != ATYPE_SMALL) {
		mono_mb_emit_ldloc (mb, size_var);
		mono_mb_emit_icon (mb, MAX_SMALL_OBJ_SIZE);
		max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
	}

	/*
	 * We need to modify tlab_next, but the JIT only supports reading, so we read
	 * another tls var holding its address instead.
	 */

	/* tlab_next_addr (local) = tlab_next_addr (TLS var) */
	tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
	EMIT_TLS_ACCESS (mb, tlab_next_addr, tlab_next_addr_offset);
	mono_mb_emit_stloc (mb, tlab_next_addr_var);

	/* p = (void**)tlab_next; */
	p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
	mono_mb_emit_ldloc (mb, tlab_next_addr_var);
	mono_mb_emit_byte (mb, CEE_LDIND_I);
	mono_mb_emit_stloc (mb, p_var);
	
	/* new_next = (char*)p + size; */
	new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
	mono_mb_emit_ldloc (mb, p_var);
	mono_mb_emit_ldloc (mb, size_var);
	mono_mb_emit_byte (mb, CEE_CONV_I);
	mono_mb_emit_byte (mb, CEE_ADD);
	mono_mb_emit_stloc (mb, new_next_var);

	/* if (G_LIKELY (new_next < tlab_temp_end)) */
	mono_mb_emit_ldloc (mb, new_next_var);
	EMIT_TLS_ACCESS (mb, tlab_temp_end, tlab_temp_end_offset);
	slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);

	/* Slowpath */
	if (atype != ATYPE_SMALL)
		mono_mb_patch_short_branch (mb, max_size_branch);

	mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
	mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);

	/* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
	mono_mb_emit_ldarg (mb, 0);
	mono_mb_emit_ldloc (mb, size_var);
	if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
		mono_mb_emit_icall (mb, mono_gc_alloc_obj);
	} else if (atype == ATYPE_VECTOR) {
		mono_mb_emit_ldarg (mb, 1);
		mono_mb_emit_icall (mb, mono_gc_alloc_vector);
	} else {
		g_assert_not_reached ();
	}
	mono_mb_emit_byte (mb, CEE_RET);

	/* Fastpath */
	mono_mb_patch_short_branch (mb, slowpath_branch);

	/* FIXME: Memory barrier */

	/* tlab_next = new_next */
	mono_mb_emit_ldloc (mb, tlab_next_addr_var);
	mono_mb_emit_ldloc (mb, new_next_var);
	mono_mb_emit_byte (mb, CEE_STIND_I);

	/*The tlab store must be visible before the the vtable store. This could be replaced with a DDS but doing it with IL would be tricky. */
	mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX);
	mono_mb_emit_op (mb, CEE_MONO_MEMORY_BARRIER, StoreStoreBarrier);

	/* *p = vtable; */
	mono_mb_emit_ldloc (mb, p_var);
	mono_mb_emit_ldarg (mb, 0);
	mono_mb_emit_byte (mb, CEE_STIND_I);

	if (atype == ATYPE_VECTOR) {
		/* arr->max_length = max_length; */
		mono_mb_emit_ldloc (mb, p_var);
		mono_mb_emit_ldflda (mb, G_STRUCT_OFFSET (MonoArray, max_length));
		mono_mb_emit_ldarg (mb, 1);
#ifdef MONO_BIG_ARRAYS
		mono_mb_emit_byte (mb, CEE_STIND_I);
#else
		mono_mb_emit_byte (mb, CEE_STIND_I4);
#endif
	}

	/*
	We must make sure both vtable and max_length are globaly visible before returning to managed land.
	*/
	mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX);
	mono_mb_emit_op (mb, CEE_MONO_MEMORY_BARRIER, StoreStoreBarrier);

	/* return p */
	mono_mb_emit_ldloc (mb, p_var);
	mono_mb_emit_byte (mb, CEE_RET);

	res = mono_mb_create_method (mb, csig, 8);
	mono_mb_free (mb);
	mono_method_get_header (res)->init_locals = FALSE;

	info = mono_image_alloc0 (mono_defaults.corlib, sizeof (AllocatorWrapperInfo));
	info->gc_name = "sgen";
	info->alloc_type = atype;
	mono_marshal_set_wrapper_info (res, info);

	return res;
}
Exemplo n.º 3
0
static MonoMethod*
create_allocator (int atype, int offset)
{
	int index_var, bytes_var, my_fl_var, my_entry_var;
	guint32 no_freelist_branch, not_small_enough_branch = 0;
	guint32 size_overflow_branch = 0;
	MonoMethodBuilder *mb;
	MonoMethod *res;
	MonoMethodSignature *csig;
	AllocatorWrapperInfo *info;

	if (atype == ATYPE_STRING) {
		csig = mono_metadata_signature_alloc (mono_defaults.corlib, 2);
		csig->ret = &mono_defaults.string_class->byval_arg;
		csig->params [0] = &mono_defaults.int_class->byval_arg;
		csig->params [1] = &mono_defaults.int32_class->byval_arg;
	} else {
		csig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
		csig->ret = &mono_defaults.object_class->byval_arg;
		csig->params [0] = &mono_defaults.int_class->byval_arg;
	}

	mb = mono_mb_new (mono_defaults.object_class, "Alloc", MONO_WRAPPER_ALLOC);
	bytes_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
	if (atype == ATYPE_STRING) {
		/* a string alloator method takes the args: (vtable, len) */
		/* bytes = (sizeof (MonoString) + ((len + 1) * 2)); */
		mono_mb_emit_ldarg (mb, 1);
		mono_mb_emit_icon (mb, 1);
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_icon (mb, 1);
		mono_mb_emit_byte (mb, MONO_CEE_SHL);
		// sizeof (MonoString) might include padding
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, chars));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_stloc (mb, bytes_var);
	} else {
		/* bytes = vtable->klass->instance_size */
		mono_mb_emit_ldarg (mb, 0);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoVTable, klass));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoClass, instance_size));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		/* FIXME: assert instance_size stays a 4 byte integer */
		mono_mb_emit_byte (mb, MONO_CEE_LDIND_U4);
		mono_mb_emit_stloc (mb, bytes_var);
	}

	/* this is needed for strings/arrays only as the other big types are never allocated with this method */
	if (atype == ATYPE_STRING) {
		/* check for size */
		/* if (!SMALL_ENOUGH (bytes)) jump slow_path;*/
		mono_mb_emit_ldloc (mb, bytes_var);
		mono_mb_emit_icon (mb, (NFREELISTS-1) * GRANULARITY);
		not_small_enough_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
		/* check for overflow */
		mono_mb_emit_ldloc (mb, bytes_var);
		mono_mb_emit_icon (mb, sizeof (MonoString));
		size_overflow_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
	}

	/* int index = INDEX_FROM_BYTES(bytes); */
	index_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
	
	mono_mb_emit_ldloc (mb, bytes_var);
	mono_mb_emit_icon (mb, GRANULARITY - 1);
	mono_mb_emit_byte (mb, MONO_CEE_ADD);
	mono_mb_emit_icon (mb, shift_amount (GRANULARITY));
	mono_mb_emit_byte (mb, MONO_CEE_SHR_UN);
	mono_mb_emit_icon (mb, shift_amount (sizeof (gpointer)));
	mono_mb_emit_byte (mb, MONO_CEE_SHL);
	/* index var is already adjusted into bytes */
	mono_mb_emit_stloc (mb, index_var);

	my_fl_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
	my_entry_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
	/* my_fl = ((GC_thread)tsd) -> ptrfree_freelists + index; */
	mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
	mono_mb_emit_byte (mb, 0x0D); /* CEE_MONO_TLS */
	mono_mb_emit_i4 (mb, offset);
	if (atype == ATYPE_FREEPTR || atype == ATYPE_FREEPTR_FOR_BOX || atype == ATYPE_STRING)
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, ptrfree_freelists));
	else if (atype == ATYPE_NORMAL)
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, normal_freelists));
	else if (atype == ATYPE_GCJ)
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, gcj_freelists));
	else
		g_assert_not_reached ();
	mono_mb_emit_byte (mb, MONO_CEE_ADD);
	mono_mb_emit_ldloc (mb, index_var);
	mono_mb_emit_byte (mb, MONO_CEE_ADD);
	mono_mb_emit_stloc (mb, my_fl_var);

	/* my_entry = *my_fl; */
	mono_mb_emit_ldloc (mb, my_fl_var);
	mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
	mono_mb_emit_stloc (mb, my_entry_var);

	/* if (EXPECT((word)my_entry >= HBLKSIZE, 1)) { */
	mono_mb_emit_ldloc (mb, my_entry_var);
	mono_mb_emit_icon (mb, HBLKSIZE);
	no_freelist_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);

	/* ptr_t next = obj_link(my_entry); *my_fl = next; */
	mono_mb_emit_ldloc (mb, my_fl_var);
	mono_mb_emit_ldloc (mb, my_entry_var);
	mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
	mono_mb_emit_byte (mb, MONO_CEE_STIND_I);

	/* set the vtable and clear the words in the object */
	mono_mb_emit_ldloc (mb, my_entry_var);
	mono_mb_emit_ldarg (mb, 0);
	mono_mb_emit_byte (mb, MONO_CEE_STIND_I);

	if (atype == ATYPE_FREEPTR) {
		int start_var, end_var, start_loop;
		/* end = my_entry + bytes; start = my_entry + sizeof (gpointer);
		 */
		start_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
		end_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
		mono_mb_emit_ldloc (mb, my_entry_var);
		mono_mb_emit_ldloc (mb, bytes_var);
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_stloc (mb, end_var);
		mono_mb_emit_ldloc (mb, my_entry_var);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoObject, synchronisation));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_stloc (mb, start_var);
		/*
		 * do {
		 * 	*start++ = NULL;
		 * } while (start < end);
		 */
		start_loop = mono_mb_get_label (mb);
		mono_mb_emit_ldloc (mb, start_var);
		mono_mb_emit_icon (mb, 0);
		mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
		mono_mb_emit_ldloc (mb, start_var);
		mono_mb_emit_icon (mb, sizeof (gpointer));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_stloc (mb, start_var);

		mono_mb_emit_ldloc (mb, start_var);
		mono_mb_emit_ldloc (mb, end_var);
		mono_mb_emit_byte (mb, MONO_CEE_BLT_UN_S);
		mono_mb_emit_byte (mb, start_loop - (mono_mb_get_label (mb) + 1));
	} else if (atype == ATYPE_FREEPTR_FOR_BOX || atype == ATYPE_STRING) {
		/* need to clear just the sync pointer */
		mono_mb_emit_ldloc (mb, my_entry_var);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoObject, synchronisation));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_icon (mb, 0);
		mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
	}

	if (atype == ATYPE_STRING) {
		/* need to set length and clear the last char */
		/* s->length = len; */
		mono_mb_emit_ldloc (mb, my_entry_var);
		mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, length));
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_ldarg (mb, 1);
		mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
		/* s->chars [len] = 0; */
		mono_mb_emit_ldloc (mb, my_entry_var);
		mono_mb_emit_ldloc (mb, bytes_var);
		mono_mb_emit_icon (mb, 2);
		mono_mb_emit_byte (mb, MONO_CEE_SUB);
		mono_mb_emit_byte (mb, MONO_CEE_ADD);
		mono_mb_emit_icon (mb, 0);
		mono_mb_emit_byte (mb, MONO_CEE_STIND_I2);
	}

	/* return my_entry; */
	mono_mb_emit_ldloc (mb, my_entry_var);
	mono_mb_emit_byte (mb, MONO_CEE_RET);
	
	mono_mb_patch_short_branch (mb, no_freelist_branch);
	if (not_small_enough_branch > 0)
		mono_mb_patch_short_branch (mb, not_small_enough_branch);
	if (size_overflow_branch > 0)
		mono_mb_patch_short_branch (mb, size_overflow_branch);
	/* the slow path: we just call back into the runtime */
	if (atype == ATYPE_STRING) {
		mono_mb_emit_ldarg (mb, 1);
		mono_mb_emit_icall (mb, mono_string_alloc);
	} else {
		mono_mb_emit_ldarg (mb, 0);
		mono_mb_emit_icall (mb, mono_object_new_specific);
	}

	mono_mb_emit_byte (mb, MONO_CEE_RET);

	res = mono_mb_create_method (mb, csig, 8);
	mono_mb_free (mb);
	mono_method_get_header (res)->init_locals = FALSE;

	info = mono_image_alloc0 (mono_defaults.corlib, sizeof (AllocatorWrapperInfo));
	info->gc_name = "boehm";
	info->alloc_type = atype;
	mono_marshal_set_wrapper_info (res, info);

	return res;
}